Jason Kokrak earned a record lead at the AT&T Byron Nelson as two-time major champion Jordan Spieth sensationally missed the cut.
Kokrak was the star performer on Friday after carding an almost flawless eight-under-par 62.
The American's performance saw him move five shots clear to 12 under atop the leaderboard – the greatest 36-hole lead at the PGA Tour tournament since David Love III's four-stroke advantage in 2000.
Billy Horschel (65) is second heading into the weekend, but world number one Dustin Johnson is lurking in Irving, Texas.
U.S. Open champion Johnson posted back-to-back 67s to be tied for third at six under following the second round.
Teeing off on the back nine, Johnson was flawless as he birdied the 18th before adding another three consecutive birdies from the fifth to the seventh at Four Seasons Resort and Club Dallas.
Johnson would have been five shots adrift had he not bogeyed his final hole.
An Byeong-hun (66), Cameron Tringale (68), Bud Cauley (67), overnight leader James Hahn (70) and Jhonattan Vegas (68) are also six under.
Former world number one Jason Day is nine shots behind Kokrak following his second-round 69.
Masters winner and defending champion Sergio Garcia posted a five-under-par 65 to be two under through 36.
However, it was a day to forget for Spieth after he farewelled the tournament.
Spieth fired a five-over 75 with a quadruple-bogey nine on the par-five 16th hole as he missed the cut for the third time in four starts.
Spieth was well inside the cut line before the implosion that forced him to re-tee twice.
|Kante comfortable with surprise new Chelsea role|
|Rugby Championship 2018: The numbers behind New Zealand´s dominance|
|LaLiga 2018-19: Bale ready to be Madrid´s shining light after five years in Ronaldo´s shadow|
|Rodgers unimpressed by absence of ´fit´ Boyata|
|Braves´ Acuna Jr. has arrived as a true MLB star|
|LA Galaxy 2 Colorado Rapids 2: Jackson´s deflected strike sees spoils shared|
|Victory offer postponed retirement, says Honda|
|Kyrgios forgets tennis shoes, Federer back in business|
|Williams knocked out as Garcia and Pliskova advance in Ohio|
|Kvitova sees off Serena in Cincinnati classic|
|Federer dispatches Gojowczyk in Cincinnati|
|Stead succeeds Hesson as New Zealand coach|
|Duminy encouraged despite South Africa´s mixed results|
|Thiem withdraws from Cincinnati Masters|
|Edwards joins Ospreys in consultancy role|
|Former Arsenal and Barcelona player Song joins Sion|
|I´m very happy with what I have - Spalletti not desperate for Modric|
|Roethlisberger evaluated for concussion after practice|
|Brady ´absolutely´ expects to face Eagles|
|Rugby Championship 2018: Reasons for optimism and concern for Australia|
|Wentz ´gonna be close´ for Eagles opener|
|Cleveland ´victory fridges´ to unlock beer if Browns finally win|
|England´s Watson suffers injury setback|
|Mariners reinstate Cano after 80-game suspension|
|AEK Athens 2 Celtic 1 (3-2 agg): Rodgers´ men dumped out of Champions League|
|Alonso to leave F1: Paddock reacts to Spaniard´s exit|
|Roma sign midfielder N´Zonzi from Sevilla|
|Alonso to leave F1: Who will replace Fernando at McLaren?|
|Extraordinary Zidane is in Real Madrid´s past - Lopetegui|
|Alonso to leave F1: Then and now - how the grid, teams and calendar have changed since 2001|
|Wawrinka and Azarenka receive US Open wildcards|
|Parma sign Napoli pair Inglese and Grassi on loan|
|Sandakan castles Proteas before Sri Lanka squeeze home|
|Ronaldo sale won´t stop Real Madrid winning - Ramos|
|Predators sign Ryan Ellis to eight-year, $50M contract|
|Curran, Woakes, Rashid - who makes way for Stokes in England´s Test XI?|
|Griezmann well positioned for Ballon d´Or, says Simeone|
|Criscito: I was on Genoa bridge shortly before collapse|
|Alonso to leave F1: How the Spaniard´s numbers stack up to the greats|
|Rookie LB Roquan Smith finally signs Bears contract|
|De Villiers enjoying relief from ´unbearable´ Proteas pressure|
|Fernando Alonso to leave F1|
|Spalletti extends Inter contract|
|Godin, Koke, Griezmann and Juanfran named Atletico Madrid captains|
|Ronaldo out of hospital after illness|
|Fury: Beating Wilder and Joshua ´very easy´|
|Dickinson retires to take up academy coaching role|
|Cricket the ´sole focus´ for Stokes as he returns to England squad|
|Cheryshev moves to Valencia on loan|
|Mandzukic retires from Croatia duty after World Cup|
|Ben Stokes found not guilty of affray|
|Tottenham issue new stadium update and apology to fans|
|Chelsea flop Bakayoko moves to AC Milan on loan|
|Gabi urges Al Sadd team-mate Xavi to play on|
|Ronaldo leads UEFA Goal of the Season nominees|
|Federer: Djokovic could be caught up in US Open pressure|
|Ronaldo to Juventus a huge boost for Serie A – Matthaus|
|Werner would welcome Ozil Germany return|
|´Perfectionist´ Serena admits to ´unrealistic´ expectations in tennis and motherhood|
|Klopp praises Deschamps and his ´boring´ France|
|LaLiga 2018-19: Bale or Griezmann - Who will step into Ronaldo´s breach as Messi´s main rival?|
|Woods winning 15th major would be greatest comeback in sport – Faldo|
|Retiring Storm great Hoffman not giving up on Finals dream|
|Folau won´t change aerial approach in All Blacks showdown|
|Racism behind Sterling criticism, says ex-Arsenal star Wright|
|Eto´o joins Qatar SC following Ligue 1 links|
|UEFA Super Cup 2018-19: Atletico academy eclipsing Madrid, La Masia|
|UEFA Super Cup 2018-19: Should Real Madrid cash in on Modric?|
|Scintillating Serena sends warning, Azarenka survives opener|
|DeGrom strikes out 12, Mets hit 5 homers in win over Yankees|